Experimental Study Of SO₂ Removal By Char Supported Iron Oxide

With the development of our economic, the environmental pollution problem is getting worse. The air pollution problems caused by SO₂ coming from the utilization of coal sverely affected the atmospheric environment and human life. In order to control SO₂ emissions, a viable and low-cost sorbent was preparied for removal of sulfur oxide in the flue gas.Biomass and lignite mixed chars were impregnated with Fe?NO3?3 to get the activated char desulfurization sorbentusing co-gasification method in this paper. The characteristics of desulfurization sorbent have been investigated by using a fixed bed experimental apparatus. The specific surface area and crystal structure of the sorbents were characterized by BET and SEM before and after desulfurization.The results showed that biomass and lignite co-gasification char supported Fe₃O₄ has a good desulfurization activity, and the sorbent supported 10% Fe can be reached to the highest desulfurization efficiency and sulfur capacity?764.1mg/g? in the presence of O₂ and H₂O. Although the particle size of 0.075⁰.125 mm has the longest penetration and the maximum sulfur capacity, in consideration of the complexity of the technology and industrial applications, it is recommended to select 0.5⁰.9mm diameter desulfurization sorbent; Desulfurization sorbent prepared by different carriers on SO₂ removal performance comparison is as follows: L-Fe10> BL-Fe10> B-Fe10; The rise of temperature is not conducive to the adsorption of SO₂ molecule and formation of active site, taking into account the actual power plant flue gas temperature is generally about 120?, it is recommend using the bed temperature 100 ?.In the process of SO₂ adsorption, oxygen was first chemical adsorbed on the char's surface, forming C?O? complex which were used as active sites. Metal oxide promoted oxygen chemical adsorption on the char surface to form more active sites which made the oxidation of SO₂ to SO₃, the generation of sulfuric acid and a small amount the metal sulfate?Fe₂?SO₄?₃?stored in the char microspore structure in the presence of water vapor.